Timing mechanism



June 4, 1935. M. s. CURTIS TIMING MECHANISM Filed Aug. 26, 1950 June 4, 1935. r M. s. CURTIS 2,004,038

TIMING MECHANISM Filed Aug. 26, 195o f 2 sheets-sheet 2 l NTOR Patented June 4, 1935 UNITED STATES v MECHAMSM j MyronV S. Curtis,Pawtucket,fR; I., assignor to William-Wallaoe Potter, Pawtucket,` Rf AI.

applicati@ August 36,1930, seria1no.477,8s1-

'l solaires@(CLM-432s) My I invention relates to` improvements "of timing mechanisms such for examplel as are described in my U. S. Patent No. 1,211,551.

These timing mechanisms have, for their purpose, the control of the relations between ltwo shafts, or `rotating elements, one driven from ,the

other, through a lclutch by which the driven ele-j ment may be clutched to orde-'clutched from theV driving element, or may be reversibly clutched to `1()v the driving element, so that always the ltwo elements will have an exact relation of rotation; To maintain this relation, it is necessary ltheft the driven element bev clutchedto and declutched from the driving element with the parts always in the same Aradial position and that the driven element, when de-'clutched, be positively positioned and remain in this positive position while declutched.

It is also necessary, in order to obtain these results that the mechanism for clutching and declutching (and for counting the number of revolutions between such movements) be positively driven and controlled from the driving element.

My present invention has, for its object, the attainment of the results above set forth, and consists in whatever is defined by or is within the scope of the claims.

Referring to the drawings: Fig. l is a front elevation ofl a so-called timing box, embodying my invention;

Fig. 2 is an end elevation with a portion of the end wall removed;

Fig. 3 is a cross section, through the gearing with the shafts displaced from their actual positions, for clarity of illustration;

Fig. 4 is a cross section on the line 4-4 of Figs. 1 and 3;

Fig. 5 is a cross section substantially on the line 5-5 of Fig. 4.

Describing the embodiment of my inventionv shown in the drawings by way of illustration and not limitation, a casing, I8, has rotatably located in it, the driving element or shaft, II, which receives power from some outside source, and which has keyed to it sleeve I2, one end of Whichis provided with clutch teeth which mesh with corresponding clutch teeth on the hub of gear I 3,

which gear is connected with and drives, gear I4 I through tongue I5. The sleeve I2, and gears I3 and I4 are held between a collar I -cn shaft II,

and nuts I'I on the same shaft, the Whole forming an assembled unit with Ashaft I I. Gear I4 meshes with and drives gear i8, which revolves loosely on shaft I9, which shaft is free to slide Vin casing I0, but is held from rotating by means presently described. Gear I3 drives gear 20 in an opposite directiontogear I8, through an intermediate pinion`2l, which is keyed to shaft 22. The ratio between, gears I3 and 20 is exactly the same as the ratio between gears I4 and I8. 5 Gear 20 also'revolves freely on shaft I9. Shaft I9 has pinned to it cam roll carrier 23, which is provided with an'extension orarm 24, the outer end of whichhas jaws that vstraddle a fixed stud 25 and Ythus shaft I9 is'heldfrom revolving while, 10 fr ee to slide longitudinally.

' Revolving freely on shaft I9, but fixed against longitudinal 4movement Vthereonisthe driven element which is a clutch gear 28, provided on its ,oppositeV faces with ,single clutch tooth spaces 21 ,and l5 28, which respectively may be caused to mesh with single teeth 29 and 3U'one each on gears I8 and 20, by longitudinal movement of shaft I9. When so meshed, gear 26 is driven either in one direction by gear I8 or in the opposite direction by gear 20. 20 Longitudinal movement is imparted toshaft I9,

by cam 3l, keyed to spider, 32, and acting on roll 33 on cam roll stud 34, secured to cam roll carrier 23.

Cam spider 32 and, therefore, cam 3I, receive 25 intermittent motion from drive shaft II. To accomplish that a cam 35, is keyed to shaft 22, (and o therefore, positively driven by shaft II, through gears I3 and 2I) whose cam path 36 coacts with pins 31 on cam 38 keyed to stud shaft 39 which 30 revolves in bushing 40 located in casing ID, in such a way that one revolution of shaft 22 causes an intermittent motion of cam 38, equal to the angle between two adjacent pins and this intermittent movement takes place during the same angular 35 movement of shaft, 22, so thatwhile camV .38 is indexing, it revolves at the same speed as shaft 22 and when through indexing,is locked stationary, by land 4I on cam 35. Cam 38 has on its periphery cam path 42 which meshes withpins 40 43 on` plate 44, which is fastened to cam spider 32 and, therefore, cam 38 indexes cam spider 32 in the same way as it is itself indexed by cam 35. Accordingly, cam spider 32 is indexed one pin during a very small `part of a rotation of shaft 45 22 and remains locked stationary until its next index, and, as cam path 45 in cam 3| is so formed as to have its complete throw during one index,A it is apparent that gear 25 will be clutched to, or de-clutched from either gear I8 orl gear 20 in 50 a very Vsmall portion of their revolution and at always exactly the same radial position of the single clutch teeth 29 and 30.

Meshing with gear I8 and driven from it, is gear 4B keyed to shaft 41, the end of which 48 is 55 an eccentric which coacts with slot IISl of 'a sliding block 5D in ways 5|, and thus as shaft 41 revolves, block is caused to reciprocate in ways 5I. Gear 26 has a flange 52 which partially surrounds it through substantially a half circle and which is in line with jaws 53, of block 50, when gear 25, is in a neutral position, but is clear of jaws 53 when gear 26 is clutched to either gear I3, or gear 20. Y

The positive gear connections areso arranged that gear 26 is shifted into neutral with the flange 52 in the position shown in Fig. 4, and when block is in its low position so that jaws, 53, are in the position shown by the dotted lines, Fig. li.l

gear 26 has revolved beyond the central or neutral position, it is recentered by jaws 53 engaging the Y lower end of iiange 52, and thereby rocking gear 46. Any radial displacement of gear, 26, while it is in the neutral position is immediately corrected by jaws 53.

The machine with which my timing box is shown in the drawings to be associated, includes a long pinion, 54 (see Figs. 1 and 2) which is in mesh with a gear, 55, forming the part of a train not requiring further description with which connection with the timing box is made. The pinion 54, is elongated because it is connected with a to and fro moving member of the machine (not shown) so that at all points in such movement it will remain in mesh with gear, 55. Pinion 54, is slidable on a shaft, 56. gear 26 and transmitted therefrom to gear 55.

Power is supplied fromV What I claim is:-

l. A mechanism for timing rotatable Vdriving anddriven members, comprising such members, means to connect and disconnect them including a rotatable clutch element, and timed automatic means to assure the same angular position of said element when de-clutched from the driving member, and having means for locating and holding the driven member in a definite position, while declutched from the driving member, comprising a to and fro moving block having jaws, opposite jaw-engaged surfaces on said driven member, and means deriving motion from the driven member to reciprocate said block.

2. The combination of a driving shaft, a rotatable axially shiftable clutch element, a coacting clutch element alining therewith, means to shift said axially shiftable clutch element, including a rotatable cam, an intermittently acting connection'between said cam and said driving shaft, and means deriving motion from said drivingshaft to assure the same angular position ofsaid shiftable clutch element when in declutched position. s Y

3. A mechanism of the character described comprising driving and driven members, a clutch having interlocking elements interposed between said members for clutching and declutching the same and means for aligning said members in clutchingposition when said members are defclutched, the said means comprising jaw-engaging surfaces on one of said members, a block provided With jaws for `engaging said surfaces,rand means for reciprocating said block to cause said jaws to periodically engage said surfaces.

MYRON S. CURTIS. 

